With the advent of the Internet, there has been a sharp increase in the demand for network bandwidth which has been principally driven by two trends: (i) the increasing number of networked computers exchanging data; and (ii) the increasing need for networked computers to exchange ever-increasing quantities of data. In response to this demand, a variety of new computer network technologies have been developed that improve upon existing technologies by increasing the efficiency of data transmission, increasing the speed of data transmission, or both. Although such technologies achieve increased network bandwidth, they also create a need for new and improved technologies to analyze networks incorporating these technologies.
Network assessment tools referred to as “analyzers” are often relied upon to analyze networks during use. One example of such analyzers is the SNIFFER ANALYZER™ device manufactured by NETWORK ASSOCIATES, INC™. All analyzers have similar objectives such as determining why network performance is slow, understanding the specifics about excessive traffic, and/or gaining visibility into various parts of the network.
Analyzers are often used to monitor networks which are based on an asynchronous transfer mode (ATM) switching protocol. ATM switching is used in communications systems for switching voice, data, and video information. Frequently, these services are supported simultaneously by the same switch. In use, ATM switches are capable of switching small elements of information, called cells, rapidly between an input port and an output port. A header at the beginning of each cell contains identifying information that may also be modified in the course of this switching. During operation, the switches typically track the switching using connection tables, stored in a specialized memory in the switch.
In the prior art, each connection supported by the switch occupies at least one entry in one or more of the connection tables. Typical analyzer tools extract these entries for gathering statistics and monitoring various network parameters. To date, such entries have been extracted one-at-a-time. In other words, typically analyzers issue one call command to extract one entry from the connection table. This one-to-one relation thus results in a vast number of calls being made to extract the necessary data.
Since typical scanning is carried out in real-time, it is often difficult to extract all of the required information in a manner efficient enough to keep up with the operation of the switch. Often, the analyzer must take incomplete “snap shots” of the contents of the connection tables. This, in turn, results in incomplete statistics and substandard scanning results.
There is thus a need for an apparatus and method for more efficiently and effectively collecting information from ATM connection tables for analysis purposes.